[Overview][Constants][Types][Classes][Procedures and functions][Index] Reference for unit 'math' (#rtl)

sumsandsquares

Return sum and sum of squares of values.

Declaration

Source position: line 0

procedure sumsandsquares(

  const data: array of Extended;

  var sum: float;

  var sumofsquares: float

);

procedure sumsandsquares(

  const data: PExtended;

  const N: Integer;

  var sum: float;

  var sumofsquares: float

);

Description

sumsandsquares calculates the sum of the values and the sum of the squares of the values in the data array and returns the results in sum and sumofsquares.

The second form of the function accepts a pointer to an array of N values.

Errors

None.

See also

sum

  

Return sum of values

sumofsquares

  

Return sum of squares of values

totalvariance

  

Return total varians of values

variance

  

Return variance of values

Example

Program Example45;

{ Program to demonstrate the SumOfSquares function. }

Uses math;

Var
  I : 1..100;
  ExArray : Array[1..100] of Float
  s,ss : float;

begin
  Randomize;
  for I:=low(ExArray) to high(ExArray) do
    ExArray[i]:=(Random-Random)*100;
  Writeln('Max             : ',MaxValue(ExArray):8:4);
  Writeln('Min             : ',MinValue(ExArray):8:4);
  SumsAndSquares(ExArray,S,SS);
  Writeln('Sum             : ',S:8:4);
  Writeln('Sum squares     : ',SS:8:4);
  SumsAndSquares(@ExArray[1],100,S,SS);
  Writeln('Sum (b)         : ',S:8:4);
  Writeln('Sum squares (b) : ',SS:8:4);
end.
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